Developing apparatus



May 19, 1953 J. SINGER DEVELOPING APPARATUS C I Z ZZZIIIIJ I 'l'liTIIlil'J Filed May 5, 1950 Patented May 19, 1953 DEVELOPING APPARATUS Alexander J. Singer, Seat Pleasant, Md. Application May 5, 1950, Serial No. 160,239

2 Claims.

This invention relates to photography, and more particularly to new and useful improvements in tanks for developing roll film.

The principal object of the invention is to provide an improved form of developing apparatus with a film holder which requires no adjustment when used for anyone of the popular sizes of roll films.

Another object of the invention is to provide a developing apparatus which is simple and economical to manufacture and which consists solely of two parts.

Still another object of the invention is to provide a developing apparatus which is simple to use in developing roll films.

Another object of the invention is to provide a developing apparatus with a detachable film holder on which any desired length of roll film may be easily and quickly'attached.

The invention embodies an elongated tank body of rectangular cross-section to which is detachably connected a film holder. The latter is provided on one end with an open-ended head member the opening of which is equipped with light arresters to prevent light from entering the tank body when the film holder is attached to the latter. The light arresters also allow free entry of liquid in filling the tank body but offer a slight resistance when the liquid is poured from the tank body.

The various features of novelty which characterize the present invention are pointed out specifically in the claims annexed to and forming a part of this specification. For a better understanding of the invention, however, its advantages and specific objects attained with its use, reference should be had to the accompanying drawings and the description which illustrate and describe a preferred embodiment of the invention.

In the drawings:

Figure 1 is an iosmetric view of a preferred embodiment of the developing device of my invention;

Figure 2 is a cross-sectional view taken along line 2-2 of Figure 1, looking in the direction of the arrows;

Figure 3 is a vertical sectional view taken along lone 3-3 of Figure 1, looking in the direction of the arrows, with a film in place; and,

Figure 4 is a vertical sectional view of the film holder when removed from the tank body and taken along line 4-4 of Figure 3.

Referring more particularly to the various figures of the drawing in which like reference characters indicate the same parts, the developing device comprises a tank body 6 and afilm holder 1. The tank body 6 is relatively long with respect to its rectangular cross-section. These parts may be made of metal, plastic, rubber, or any other suitable material which is opaque and is not affected by developing solutions or any other solutions used in developing and treating photographic films.

The tank body 6 is of such a size that the popular sizes of roll film may be suitably developed, washed and fixed therein. The film holder 1 requires no adjustingto hold the film. A cover or open-ended head member 8 is integrally formed with one end of the film holder, as shown in Figures 1, 3 and 4. The head member 8 is of larger cross-sectional area than the tank body 6 and comprises a circumferential vertical wall formed with a shoulder 5 at its lower end from which a slot or groove 9 extends inwardly and lengthwise of the member 6 to form a circumferential pocket for receiving the upper edge of the tank body 6 when the holder 1 is inserted into the tank body. It is obvious that in this manner a light tight joint is formed between the head member 8 and the tank body 6.

The lower portion of the film holder 1- is I- shaped in cross-section and is provided onthe opposite faces of its web section II with a plurality of uniformly spaced semi-circular ribs It! which preferably are integrally formed with the holder. The ends of the ribs are spaced-from the longitudinal flanges l2, as shown. The flanges l2 are connected with opposite end walls I3 of the head member 8, as shown in Figure 4. The flanges 12 preferably are spaced from the side walls and end walls of the tank body 6 when the holder is inserted in the tank. Although it is preferred to form the ribs 10 as shown, it is to be understood that the ribs 10 may have any other shape as long as the ribs provide a space for the liquid used to develop and flush the film l4 attached to the holder '1. The semi-circular ribs serve the dual function of preventing the film from adhering to the film holder and to promote agitation when the film is washed.

The open-ended head member .8 is provided with integrally formed light arrestersl5 as'show'n in Figures 3 and 4. The light arresters extend the full width of the rectangular opening in the head member 8 and are alternately vertically spaced and arranged to overlap with their free margins to prevent light from entering the tank body 6 during the developing of the film. The light arresters 15 allow for the free entry of the liquid but are arranged to extend at an acute angle inwardly so as to offer a slight resistance when the liquid is being poured from the tank in order to create an agitating effect when washing the film. A vertical transverse partition I8 integrally formed with the head member 8 and extending across the light arresters I5 and parallel to one end wall provides'a vent H to eliminate air binding when filling the tank body with liquid. The larger portion l8 of the opening of the head member 8 serves for filling and emptying the tank body.

In utilizing the developing tank, the film holder '1 is first removed from the tank body 6-. Most roll films have a water-proof adhesive tape 19 at one end, and by means of this tape thefilm is secured with the sensitizedlside outto the, film holder 1 just below the head 8 to the Web ll of the film holder as shown in Figure 3. film is then extended down to the bottom end of the holder 1. and is brought around to the other side of the web. l l to be aifiXed-Withits otherend by means of another piece of adhesive tape Hi. In this-mannerthe film l4 may be quickly and easily attached to the holder 1 even in total darkness which is necessarywith some types of films.

The film holder 1 with the film attached thereto is then inserted in the tank body 6. Developing fluid is then poured into the opening 18 to the level indicatedwith 20v in Figure 3. The filmis then suitably developed as, is Well understood in the art and liquid may be suitably agitated. After the film has been treated the required length of time the developing fluid is poured from the opening. 18, after which a washing fluid is poured into the tank and removed-again to be replacedby a fixing solution to fix the film in the usual manner. In fillingand emptying of the developing tank, the vent ll prevents air binding. Furthermore, .with this construction after the film has once been positioned in the developing tank, the developing, washing and fixing may be accomplished indaylight or ordinary room lightingand total darkness is no longer required.

It is thus obviousv that a developing tank has been disclosed which is not only particularly desirable for developing of long roll film whichneed to be positioned on both sides of the holder, but also is equallyadesirable for shorter roll films which may be attached toone side of the frame only.

Furthermore, a simple developing: tank has been disclosed in which no adjustments are required for different sizes and lengths of roll film. Obviously, also, as thereareno .movable parts and since the device comprises only two parts, a developing tank has been provided which may be simply and quickly operated.

In addition the developing tank may be constructed very economically, is simple to load with film in the darkness and may thereafter be used in daylight without the film becoming logged,

While in accordancewith the provisions of the statutes, I have illustrated and described the preferred embodiment of my invention now known to me, it will be apparent to those skilled inthe art that changes may be made in the form of The roll.

the parts of the developing device disclosed and in the arrangements of the several details without departing from the spirit of the invention as long as these changes remain within the scope of the claims accompanying this specification.

What I claim is:

1. A film holder for a developing tank comprising an elongated member of I-shaped cross section and a cover provided with a rectangular opening integrally formedwith oneend of said elongated member, said cover having an outwardly directed shoulder where it is connected with said elongated member, said shoulder being --providedwith a continuous groove for receiving the upper edge of a developing tank into which said filmholder is adapted to be inserted, the

I-shapedacross section of said elongated member having flanges between which a web section is positioned on which a film strip to be developed is adapted to be secured, one end of said flanges being,connected with said: coverinside thearea --circumscribed.by said continuous groove, light arresting ribs. extending. along .the entire width of said. opening andia transverse partition being provided in theopening. of said cover, near one of the narrow. walls of thev same to form a lightproofzvent. 2. A film holder for a developing tank com- "prising' anv elongated .memberof I-shaped cross section and a cover p-rovided with a rectangular opening integrally formed with one end of said elongated member, the opening in said cover being substantially .as wide as. the, largestdimension of the cross section oisaid elongated member, said cover having an outwardly directed shoulder where. ityis connected with said elon gated-member, said shoulder being provided with a continuous-,groove-for receiving the upper edge of a developing. tank into whichsaid film'holder isadapted tobe inserted, the I-shaped cross section of ,said elongated,.membe,r havingfianges between which a.;web. section is, positioned on which afilm. strip .to: be developed is adapted to be secured, one end of. said flanges-.beingconnested-with said cover inside the. area circumscribed by said continuous groove, light arresting ribsextendingralong.the entire width of said opening and a,...transverse. partition being provided in the .openingrofr said cover, near one of the narrow walls of the same to form alightproof vent.

ALEXANDER' J. SINGER.

References Cited in.--the file of this patent UNITED STATES PATENTS 

